Adapter



ADAPTER Filed June 28, 1930 I, .a. m n 1.

H. BROADWELL 5 Y fingerwheel in no way injures the dial or filed April 17 1930.

Patented June 16, i931 uni men-r Es 1 PATENT o FI'cE Rowena) mtonnwnm orjnrnenwoon; :NEW JElBSEYQiASSIGNOR TO BELL' rntnrnonn, LABORATORIES, .mconromrnn; on NEW onx. N. .Y., A conronarron or new YORK I nnnrrna Application fi a'oui 28, 193p. 'Serial No. 4 4,505.

This invention relates to systems for determining variations in the speed of a rotating telephone dial by intermittently observmg a 'stroboscopic target: secured to the dial and particularly to the means employed in securing the target to the dial; V

A stroboscopic system to which this inventionis particularly adapted is disclosed in my oo-pending application Serial No. 445,182,

The system disclosed in" the above men- 'tioned co-pending application comprises a specially designed stroboscopic target which is adapted to be mounted on the'finger wheel of a telephone dial andintermittently viewed through the vibrating tines'of a tuning fork,

or by means of an interrupted light source. In such a system it is essential that the target be rigidly secured tothe finger wheel" in a removable manner,' and as such stroboscopic tests are made in the field it is also necessary that the association oi the target with the marsits finishj It is also requisite that the target mounting'means be of such itinature that-dials 'havingvarying thicknessesof paint may be tested and the target securedther'eto in a'rigid manner.

' It is therefore the object ofthisinvention with the dialand' its "dissociation therefrom without scratching or in any way '.marri'n the f nish on the dial-finger when? i This object isattained inaaccordance with a feature of-theinventio'n by the provision V v of a target provided Wit 111:3; pluralityof'cooperating grippingprongs which are adaptedto engage'the inner periphery of certain of the holeslinithe .dialfinger-wheel to st. cure the target to'tlie dial'and of means for y distending' said prongs for preventing an forcible engagementthereof with any part of the finger-wheel during the mounting of ings in which Fig. l'shows how the st -roboscopic target is observed through a tuning fork Fig. 2 isa view ofthetarget per'se; Fig. 3 is a sectional view of the targetmounting or adapter; Fig. 4 is a perspective view of a telephone dial with which the target adapter functions and Fig. 5 is a perspectiveview of the underside of the target adapter.

In; the following description particular reference is made to Figs. 3 and 5.

The stroboscopic target 6 per se, comprises a circularrmetallic disc upon either side of a which is pasted or'otherwise secured a circular sheet upon which the target indications havebeenplotted. v a

The gripping mechanism "consists of a cross-shaped spring member 9 secured by means of rivets 10 to a circular disc 8. Holes,

such as 15; 16-and 17 inthe cross-shaped sprlng member 9Tthrough which the rivets v10 pass aremade as elongated slots in order that the arms of the member 9 may eXper- .ience a relatively small sliding movement when the gripper is actuated, aswill hereinafter appear. i

Each arm of the member 9 is provided with an integral depending portion constitutinga snap-prong such as 11, 12, 13' and 14; A cup shapedflpost 19 is staked to an extension 4 of thecircular disc 8 and serves to determine theposition of the "target on the dial as will;

bedes'cribedlater.

i Centrally located on and'securely staked to V the disc 8 is a hollow screw member 7 which is adaptedto passthrough the center hole '25 inthetarget and cooperate with an internally'threaded knurled knob 21 in securing the target to the adapter.

A pin or .pluhger QO is slidably contained Within the hollow screw member 7, its head normally resting uponthe center of the cross- Q shaped mernberil, asshown in Fig. 3, and is. prev entedirom' falling out by ,means of F shoulders withinthe screw member 7; a 1 TheknobQl isprovided with cylindrical cavity 22 in which a T-shapedbutton 26 is movably mounted. A set-screw 27 fitting 1 into the'side of knob 21 and projecting with- ;in the cavity 22 prevents the removal of the actuating button 26, at the same time permitting a sliding movement thereof.

In normal position, the cross-shaped spring member 9 maintains the head of pin 20 flush against the shoulders within the screw 7 and the pin 20 is of such a length, that under this condition it extends within the cavity 22 of the knob 21 and impinges against the under surface of the button 26, so that the button 26 is raised to the position shown in Fig. 3.

When it is desired to make a test on a dial 40 such as is shown in Fig. 4, the knob 21 of the assembled unit shown in Fig. 3 is conveniently grasped by the tester, with his thumb depressing the button 26 causing it to slide in the knob cavity 22, whereupon the pin 20 is moved in a downward direction, its head bearing upon the center portion of spring member 9. The mid-section of the gripper 9 is forced away from the disc 8 and the four prongs 11, 12, 13 and 14 move outwardly or are distended, the four small rivets 10 acting as points of leverage. The dash lines in Fig. 3 show the position of the gripper 9 and its associated prongs when in its actuated condition. The arcuate portion 42 of post 19 is then inserted, at an angle, in the Zero hole 43 of the finger wheel 44, the shoulder portion 41 and associated flange partially resting upon the outer edge of the hole and the upper surface of the finger wheel to serve as a pivot. Due to the expansion of the gripper, the prongs 11, 12, 13 and 14 will clear the inner peripheries of holes 48, 47, 46 and 43 respectively of the finger wheel 44 while the target is being normally positioned on the dial. When the prongs have entered their respective holes the button 26 is released whereupon the gripper 9 assumes its normal condition causing the prongs to retract and tightly grip the inner periphery of the finer holes. To remove the target from the ial, the button 26 is depressed whereupon the grippingprongs are againdistended and moved out of engagement with their respective holes; the target adapter is then lifted bodily, clear of the finger wheel.

' By use of this style of target adapter it is apparent that there is no sliding engagement between the gripper prongs and the finger wheel due to the gripping action of the prongs either upon association of the target with the dial or upon its removal therefrom,

thereby preventing rubbing of the engaging surfaces and the consequent marring of the finger wheel finish.

are rounded or arc-shaped. in such a manner as to take the torque and prevent sliding. The solid finger or post 19 is to indicate the zero hole in'ihe finger wheel and also to take the slam when the dial is fully wound up.

What is claimed is:

1. In combination, a telephone dial having a finger wheel, a disc, means for securing dial comprising a plurality of distendable prongs adapted to engage the inner peri hcry of certain holes in said finger whee a handle, and means embodied in the structure of said handle for distending said prongs to facilitate the association of said disc with the finger wheel of said dial.

3. The combination of an adapter for mounting a target on the finger wheel of a telephone dial comprising a disc, a crossshaped spring member having a plurality of snap-prongs integrally formed therewith secured to said disc and means for flexing the center portion of said cross-shaped s ring member to eflect a relative spreading 0 said snap-prongs.

4. In combination with a telephone dial having a finger wheel, a disc to be removably mounted on said finger wheel, a second disc, a screw secured to said second disc and extendin through a hole centrally located in said rst disc, a knob cooperating with said screw to securely join together both said discs, a plurality of prongs secured to the underside of said second disc and adapted to be associated with the holes in said finger wheel, and means embodied in the structure of said knob for distending said prongs to facilitate their association with the holes in the finger wheel of said dial and to efiect the mounting of said first disc on said dial.

5. In combination with a. telephone dial having a finger wheel, a disc to be removably mounted on the finger wheel of said dial,,an

. adapterfor mounting said disc on said finger wheel including a lurality of integrally associated prongs a apted to fit in certain of the holes in said finger wheel, a knob cooperating with said adapter for securing said disc thereto, a plunger, and means housed in said knob for actuating said plunger to cause the distention of said prongs to facilitate their association with certain of the holes in said finger wheel.

6. -In combination with a telephone dial having a finger wheel, a disc to be removably mounted on the finger wheel of said dial, It will be noted that the prongs 12 and 14 an adapter for mounting said disc on said finger wheel including a plurality of integrally associated prongs adapted to fit iii certain of the holes in said finger wheel, a knob having a cylindrical cavity centrally located in the head thereof, cooperating with said adapter in securing said disc thereto, a

plunger operatively associated with said prongs and means located in the cavity in said knob foractuating said plunger to cause the distention of said prongs to facilitate a theirassociation with certain of the holes in said finger wheel.

7.'In combination with a telephone dial having a finger wheel, a disc to be removablyr mounted on the finger wheel of said dial, an adapter for mounting said disc on said finger 7 wheel including a plurality of integrally associated prongs adapted to fit in certain of r the holes in said finger wheel, a knob having a cavity therein cooperating with said adaptcilitate their association with certain'of the holes in said finger wheel. 7 In witness whereof, I hereunto subscribe my name this 25th day of June, 1930.

' HOWARD BROADWELL. 

